Extremely so. For one, it actually jumps the scroll position twice in a row when you click. Secondly, the scroll should be performed first, followed by the appearance of the dialog once the scroll is complete. Finally, it would be better to "scrollTo" the position rather than an immediate jump. This way the user has a sense of where the scroll went to relative to their starting position.

I don't believe this format works well with a scrolling page to begin with. It makes a lot more sense on full-screen apps, or on fixed navigation menus. If you really need to show a dialog further down the page, you're better off having the trigger for it be down there - not further up the page.

Most importantly, don't overuse it. Even the most complex situation should not need more than 2-3 of these. Beyond pointing out extremely critical elements to interact with, the page or app shouldn't be that difficult to navigate.

Hmm, I don't have this problem. Are you talking about the introjs.com demo page?